Electric welding machine



f. (3. `GALE. ELECTRIC WELDING MACHINE.

APPIICATION FILED OCT- 2l. 192|.

Patented Oct. 31, 1922.

8 SHEETS-SHEET I.

InvenTor. Francis G.Gcx|e byiw Wm AIIys.

F.'G. GALE. ELECTRIC WELDING MACHINE. A'PPIICATION FILED OCT. 2l, i921.

1,434,285. 5 I rammed CCI31',1922.

' Fi gt3.I Fi

44 g I a7 I2 sa Fgb.

nvenr. Francis @.Gcde byMSM/QM Fy. (SALE` ELECT 'LDNG IACHINE. APPu'cArioN man ocryzr. 192x.

Patented Oct. 31, 1922.

8 SHEETS-SHEET 5,

M ses .lnvenTor. Francis G Gode F. SALE.'

v'ELECUHC WELDING MACHINE. APPUCATION FILED OCT. 2l) 192i.

1,434,285,- Pat'ented Oct. 31, 1922.

8 SHEETS-SHEE] 6.

F. G. GALE.

ELECTRIC WELDING MACHINE. APPLICATION FILED ocr. 21, 192|.

y 1,434,285. Patented oet. 31, 1922.

8 SHEETS-SHED 7.

lhwenm. Frdncs G. Gu l e ,Anya

ELECTRIC WLDNG MACHINE. APPHcATmN m50 05121, 1921.

'1 ,434,285, Patented 00m. 31,1921;

8 SHEETS-SHEET 8.k

1r sin) er d Patented @et 31. 1922.

FRANCIS G. GALE, OF `WAEERVILLE, QUEBEC, CANADA..

' ELECTRIC W'ELDXNG MACHINE.

Application :Hed October 21, 1921.

Be it known that i., limbors G. Gunn, n subject oli 'the King of Great Britain, residing at Wetervilie, Province of. Quebec, Do minion ot' Canada, have invented :in Iniproveiueifit in Eieotriel Welding` lilaoliines. oi' which the following description, in onneetion with the aeeonipunying drawing. is a specification, like characters on the dreivingr representing like parts.

T his invention relates 'to electrical. weidingg; machines end has for its object to pro vide u novei inaiehine which is-eonstructe i to Wehl the ends of e igilureiity ot tubes or bars simuitzineofusiy to the side of other tube or bur. The prothirtthus `produced in the rue-.chine een be used tor various purposes where :i 'pltuilitiv or" tubes or ours to be eonneifted zit their` ends to another tube or bar.

,"2 Merely as illustriitiugir one welhknown invention unil constructed to produce un' nrt-isle` et this nature would be provided with ineens tor holdiujbr in Yproper relation the tubes or ors constituting the tiliers, und ineens for siijiport'ng the tube constituting the top er bottoni cross ruil in position so tl .i the ends of the liilers engine-e the suie t oi' the eross ruil, tube. or bur. :unl means for electrically welding siniuituneousy the ends of all the iillers to the cross ruil.

rThe above reference to lieii trziine ends is nuitleniereiv us :in illustration and not with en v intent to limit the epplirntion of the invention` :is the invention is equally well adaptable for weldin y the ends of u piurelitv ot' tubes or uurs to the side oi unotiier tube or bur, regardless of the use` to which the completed urtirle is to be put.

in order to give :in uiulerstuiuling ot the invention. i have ehosen to illus-traite it herein us it might be einboiiinl in u. innehine for nuiliin; N a welded lieti traine end. but l desire to state that the invention not 'iinited to the purtirulur embodiment iiiusin the drawings, big. i.. is u Seria). No. 593,256.

tion of e. inziehi embodying the inven .un;

Fig. 2 is e vertirui seetionsi view on substantially the line 2-2, Fig, fi;

Figs. 3 and. 4 ure front und side views of the Contact 'for engaging the enti. of the tune;

Fig. 5 is a section on the line 5-5, Fig'. e;

Fig'. G is e vieiv showing one of the oontaets for engaging the side of the tube;

Fig, T is u section on the iine 7--7, Fig. 6;

Fig. 8 is e section on the line B-8, Fig. 7;

-F 9 is a view et the automat-ie control;

Fig. l() is anton plan vien of the means 'i'or opening; end closing the circuit;

Fig. l e. section on the line lw, Fig. l0;

Fig. l2 is u view of the ey inder and piston by which the relative movements et the contacts .are eontroiied;

Fig. 13 sectional. vien' of the head of the cylinder looking toward the right, Fie. lf2;

lFigs. 14 and 15 are sections on tie iine lie-let, Fig. 12 illustrating the vaive in dit* ferent positions;

-Figz 1G is a section on the line 16ml?) Fig. i2;

Fig. l? is n. perspective view of the valve 88;

Fig. 18 u fragmentary perspeetive View of the menus for eontroiiing' the operation ot the piston Ti;

Fig, 19 is u sectionni vienY ot one of the transformers Figs. 2t) to 22% shew steps .in the operation et making u Welded. benl trarne.

Before proceedingh to describe the um`l Chine, l will refer brietiy to and Q3 which show thev product produced. on the insb chine. Fig. 22 shon's piuralitj.' oi tubes or bars '1. having their ends weicled to the side of u tube or er 2. thus making uninterrul structure of the tubes l und This invention einstruotetl to simultaneously weld the ends of any desired number of tubes or bars l tu the side oit another-tube or bnr ln Fig. 2553 zt eoustruetion is shown in which the tubes or bars l are welded at ezirh en d to the side ot' another tube or bur.

llt

yto

tubes7 thisvbeing done in order to simplify the description, but not for the purpose of limiting the invention.

The machine is constructed 'so as to produce the construction shown in Fig. 23 as well as that shown in Fig. 22. ln order to Weld simultaneously the ends of a plurality of tubes 1 to the side of a tube 27 l provide means for holding the tubes 1 in proper spaced relation and for maintaining the tube 2 in proper position to be welded to the tubes 1, and l also provide a plurality of pairs of Welding contacts, one pair for each of the tubes 1, each pair of Welding contacts com- ,prisingf a contact element adapted to sur round the tube 1 at the end thereof' which is to be welded to the side of the tube and which is referred to as a tube-endengaging contact and another contact element (referred to as a tube-sideengaging contact) adapted to engage the side of the tube 2 which is to be welded to the tube l at each side of the tube 1. l also provide a suitable transformer mechanism for each pair l of contacts constructed to send a Welding,

current from one contact of each pair to the other contact of said pair through the end of the tube 1 and side of the tube 2, the construction being such that all of the welding transformers arerendered operative simultaneously toweld simultaneously the ends of all of the tubes 1 to the side of the tube 2.

The pairs of Welding contacts, transformers, etc., are mounted on a frame #l which may have any suitable construction. The frame herein illustrated comprises two end members 5 which are connected by crossgirders 6, 7 and 8. There are two crossgirders or tie members 7 and two c-rpss-girders or tie members 8, .the reason for which will be more fully hereinafter set forth.

The machine herein illustrated is so constructed that the tubes 1 are sustained therein in an upright position while the tube 2 is in, a horizontal position at the upper ends of the -tubes 1. Figi'. 1 shows thcftubes in the position they occupy relative to each other during' the welding operation` The tubes 1 are supported at their lower ends upon a tube-supporting member 9 which is adjustably sustained inthe frame to accommodate tubes of different lengths. 'lhis tube-supporting,r member is in the form of a shelf or ledge extending across the front of the machine and having: projections at its ends adapted to enter any one of a plurality of sockets 10 formed in the frame 4. By this means the tube-supporting member 9 may be adjusted into different vertical ositions to accommodate tubes 1 of different engths.

Each pair of WeldingV contacts comprises a contact element 11 adapted to engage the side of the tube 2 and another contact elelessees ment 12 adapted toengage the upper end of a tube 1. There Will be as many of these pairs of Welding contacts 1l, 12 as there are tubes 1 to be Welded to the tube 2. ln the illustrated embodiment of the invention there are tive tubes 1 and therefore live pairs of welding contacts. Each welding Contact 11 is provided with two arms 13 that are shaped to engage the under side of the tube 2 and partially embrace the latter, said arms 75 13 of each Contact 11 thus having engagement with the side of the tube 2 at two sepa-j rated points. For this reason said contact is referred to as a tube-side-engaging con tact.

Each Welding contact 12 which engages the upper end of a tube l is arranged to be received between the arms '13 of the corre-- sponding contact 12 as Will be presently described.

The Welding contacts 11 are all secured to a girder or support 15 which extends the length of the machine and is vertically movable on the end frames '5, said girder being provided with shoes or guiding portions 16 at its end which are guided by suitable ways 17 formed on the end frames 5. The girder is yieldingly sustained by means of springs 18 which encircle posts 19 rising from brackets 2()7 said springs resting on adjustable collars 21 which screwthread into the brackets and by which the tension` of the springs can be varied Means are provided for clamping the tube 2 firmly against the arms 13 of the contacts 100 11 during the welding operation. Said clamping means herein comprises a clamping member 22 associateclwith each contact 11 and adapted to engage the top of the tube 2 and hold it firmly against the arms 105 13.l Each clamp 22 is carried by a block 23 which is slidable vertically in Ways 2st formed on a bracket 25 secured to and depending from the member 15. laclrclamping member has a link 25 pivoted thereto at 110 27 and each link is pivotally connected at 28 to an arm 29 that is pivoted at 3() to the .member 15. Each pair of arms 26, 29 constitute a toggle device, which when straightened, forces the clamping,r member 2 down- 115 Wardly. l

Means are provided for operatingT all the clamping devices 22 simultaneously and for this purpose the arms 29 are all connected to a bar 31 which in turn is connected bv a 120 link 32 to a. lever 33 that is pivoted to the member 15 at The swinging' move ment of the lever in one direction will break the toggle devices and raise the clamps 22 into the position shown in Fig. 6 and a 125 swinging movement in the other .direction will straighten the togrgles and thus brine the clamps into clamping engagement with the tube 2 as shown in Fig. 1. i

The links 26 are made adjustable as to 130 their length so as to provide for tubes 2 of dierent vertical dimension.

1When any tube 2 is clamped against the contacts 1l as shown in Fig. l it will. be .firmly retained in position until the clamps are released.

Each member 1l is connected to one of the poles of a transformer 36 and the other pole 37 of each transformer is connected to the corresponding contact that engages the end of a tube l. The connection between each welding contact l1 and its transformer is a flexible connection so as to permit the contact to have a vertical movement. This flexible connection is herein indicated at 38 and itis in the form of flexible copper or brass strips connected at one end to the contact ll and at thevother end tothe transformer pole 35. The flexibility of the strips 38 permit the necessary vertical movement of the contact l1.

The welding contacts l2 which engage the upper ends of the tubes l have a constructio'n best seen in Figs. 3, 4 and 5. Each contact comprises a fixed member or jaw 39 provided with contact surfaces 40 that engage two sides of the tube l, and a movable member or jaw 4l having faces 42 to the other sides of the tube. The form of contact shown is one adapted to receive a tube which is rectangular in cross section but if a tube of any other shape is vto-be used then the faces 40, 42 will be correspondingly shaped. The' jaw 4l is mounted in a swinging arm 43 which is p1voted to the fixed jaw at 44. This arm 43 has an opening 45 extending therethrough and the jaw 41 has a stem 46 which extends through Ato the opening, said stem being pivoted to the jaw at 47. The jaw is yieldingly held in central position by two springs 48. The arm -43 is locked inits operative position by means of a locking member 49 pivoted to the fixed jaw at 50 and adapted to enter a siot 5l formed in the'endof the arm at The member 49 has a clamping nut 52 rscrewethreaded thereto, said nut having a handle 53 by which it may be turned.

lVhen the nut is backed off then the locking member 49 can be swung out from the slot 5l thereby unlocking the arm 43 and permitting it to be opened away from the xed jaw 39. When the arm is thus in open postion a tube l may be placed against the fa'ces 40 of the fixed Iiaw after-which the arm 43 is swung into its closed position, shown in F ig. 5 and is locked therein by the member' 49. The swinging of the arm into closed position brings the faces 42 against the tube and the latter will thus he firmly clamped between the jaws 23S-)and 4l. These ja'ws have the up-standing extensions 54 which embrace the tube l near its end, said lextensions beingtapered to fit between line with eachA other.

the arms 13. The jaw 39 is secured to the pole 37 and the transformer.

As stated above there is a transformer for each pair of contacts which transformer comprises a secondary having the two terminals 35, 37 to which the Contact of a pair of welding contacts are secured as above stated.. The primary of each transformer is shown at o4 and it is formed in two parts, one situated either side of the secondary 36. Each secondary has asso-- ciated therewith a laminated core which embraces one side thereof out is insulated therefrom, each core being firmiy clamped to the transformer and operating as a start therefor.

The transformers are adjustabiy sustained on the cross girders 7, 87 provision being made for adjusting the transformers toward and from each other, so as to properly space the various welding contacts to correspond to the desired spacing of the tubes l. The transformers are `also preferably arranged in staggered relation so as to provide for adjusting them nearer together than would be possible if they were all. in The transformers are thus arranged two horizontal rows. the alternate transformers being supported at one level and the other transformers at another level. The transformers which are at the lower level are each adjustably supported on the cross girders 7 while those st-uated at the higher level are supported on the cross girder The shape of the transformers is such, however, that the pairs of welding contacts for all the transformers come in line with each other.

The transformers situated on the lower level are each suported on a base 56 which 'in turn rests on rolls 57 that are mounted on tracks 58 formed on the girder 7. The upper set of transformers are hung from supports 59 that are mounted on rolls 6G operating'on tracks 61 formed on the upper gi de ers 8. l

The transformers may thus be readiiy adjusted so that they will be properly spaced from each other. heans are provided for clamping the transformers firmly in adjusted position and for this purpose each transformer is formed with a fixed jaw 62 adapt ed to engage the edge of either thc girdcr 7 or 8, and is also provided with the movable clamping jaw 63 adapted aise to engage said girder. Each pair of cramping aws 'areA connected by a cianiping boit 654 and when the bolts are tightened "the iaws 'xviii be firinly clamped to theedges of the girders thus locking the transformers in position. These clan'iping jaws are suitably insulated from the girders to prevent any short circuiting. The machine hoi-ein illustrated is designed to make the weld by First bringing the ends lio of the tubes 1 close to but not into iirm engagement with the side of the tube-2 and then applying 1 be welding current, thus producing a sparking contact between the ends ot thevtubes l und the side ot' the tube 2, which sparking contact is continued until the side of the tube 2 where the wel'ds are to occur has been properly heated.lk The tube 2 is vthen forced into irin contactlwith the ends o'f 'the tube l, thus making the weld. Vllhen the welding current is turned on, the end of each tube 1 will be brought to weht inga temperature betore the side-of the tube 2 has been heated to welding point, e d during' the sparking Contact, the end of tue tube l will be burnt awey'more, or less, the en cessive heat developed at the enchot the tube l operating to assist in heating 'the side ot the tube 2. lllhen .the side ot the tube 2 where the weld is to occur has been properly heated, the tube 2 is forced against the endsv ot the tube 1 and the weld is completed. This operation is illustrated in Figs. 2U and 21. Fig. 2O shows the end ot a tube l closely adjacent to but not in tirm contact with the side of a tube 2. This is the position of the parts when the current is turned on. llt/hen the welding current is applied, the end of the tube 1 will become heated much more quickly than the side ot the tube 2 and because the tubes are not held in iirm conf tact, there will be a sparking action between the tubes.

'.lhis will result in burning away the end of each tube l and as the ends ot the tube 1 burn away the member lo carryingi the tube 2 is slowly moved downward so as to maintain the proper distance between the vend of the tube 1 and the side ot the tube 2 to support this sparking contact. lWhen the side ot the tube 2 where the welding is to occur has been brought to weldingl temperature then the member 15 is given a quick. downward movement to torce the tube 2 into firm engage-ment with the end ot' the tube 1 thus el'ecting the weld as shown in Fig. 21. it this time the transformer circuits are opened.

'lhe present invention includes ineensV for automatically moving; the member 15 downwardly with a slow movement during the sparking contact and then movingI it down-- 'ward with aiaster movement when. the side ol? the tube 2 has reached a welding temperature. The machine is also provide-fl with means tor automatically openiimthe circuit of the transiormers at the proper time during: the melting of the weld. l

For giving the member 15 and the tube 2 supported thereby the above-described downward movement duringr the weldingI operation, said member l5 is provided with a plurality ot inclinedl or wedge surfaces 65 which cooperate with a plurality ot wedge members 66 that are conlined between a guide 69 formed on the trame and the wedge surfaces These wedge members 66 are connected by a rod 67 held properly spaced 'l'rom each other by separators 68 mounted on said rod, During the movement of the 70 wedge members toward the right Fig. l they. will co-operate with the inclined faces 65 to 'torce the member l5 downwardly, said wedge members during` said movement being wedged between the guide 69 and the faces 7 5 During this downward movement the springs 18 are compressed and when the wedges are moved toward the left Fig. l the springs will elevate the member 15. l

The means for moving' the wedges is constructed so as to give them iirst a slow movement to the right which results in moving the tube 2 downwaldly with a slow movement, this being' the movement which the tube has during the sparking contactv alter which the wedges 9 give a more rapid movement thereby lto bring the tube 2 firmly against the ends ot the tube l to form the weld. rlhe means herein shown for this purpose comprises a cylindeu- 7() 90 in which operates a piston 7l provided with a piston rod 72 that is connected to the wedges 66. The cylinder head '73 is provided with a port 7e therein which communicates with a pipe 7 5 leading to a reser- 95 voir 7 6, said pipe having a valve 77 there in. 78 is a by-pass around the valve 77, said by-pass having a valve 79 therein. The valve 79 and the by-pass 78 are smaller than the pipe 70 and valve 77 so that when 100 the ley-pass valve is open and the other valve closed there will be a restricted coin-` munication between the chamber 76 and the cylinder 70 while when the valve 77 is open there will be a 'tree communication between 108 said chamber and cylinderA The cylinder v70 wi 'l preferably be filled with'I oil or water or some similarI liquid and as the piston is moved to the right the oil or water will be transferred trom the cylinder to the chamber v7G through either the pipe 75 or the bypass 78, and the speed at which the piston'v can move will depend upon which of the valves 77 and 79 are open. If the ley-pass valve 79 only is open then the piston will 115 have a relatively slow movement. but if the main valve 77 is open the piston can move much more rapidly.

rlhe movement of the piston to the right is secured by introducing air or gas under pressure to the left hand end of the cylinder. The cylinder head 80 at the left hand end of the .cylinder is provided with a port Slextending therethrough and is also proe vided with two otherports 82 and 83 which 126 communicate with the valve chamber 84 Jtermed within a valve housing' S5 that is secured to the end of the cylinder head. The port 82 is connected by a pipe 86 with the upper end of the chamber 7 6 and the port 130 right the roll 115 willA pass off from the.

high portion of the track onto the low portion thereby When the tube 2 hasv been brought dov/n into proper position. relative to the ends of the tube l to provide the sparking conl tact and the Wedges continue to move to the right during the sparking contactand during' the Welding operation the roll' will remain on the low portion of the track.` '5y the time the weld is completed the Wedge will be moved sufhciently to bring the roll onto the high portion of the track at the left hand in Fig. 10' thus automatically opening the Welding circuit.

l have provided herein a device forliolding the circuit open while the Wedges are returned to their .normal position and this device comprises a block vl121 'slidably mounted on the rock shaft lf2 und having a bearing against the trame so that it cannot turn on the rock shaft. mhis block is provided With a notch 122 to receive a pin Mge-)projecting Jfrom the head of the block 114. The Wedge 6G carries two stop members 12e, 125 situated to engage the block 121 at either end et the travel of the wedge. lVhen the wedge 66 has completed its move ment to the right the stop 125 engages the bloc-lr 121l and slidesi it on the rock shalt so as'to bring the pin 123 into the notch uring the movement of the Wedge to the right the low portion of tha-'track registers with the roll 115, the rock shaft `will he prevented from turning into a position to close the contacts 109, 110 by the engagement of the `pin 123 in the notch 122. When the Wedge completes-its movement to the left thestop 12e engages. the block 121 and moves the latter into the position shown in 10 thus .freeing the pin from the notch. At this time, however, the roll is in engagement with the high portion ot' the track so that the contacts 109. 110 are maintained separated from each other. The'contact 110,'however, is tree to close against the Contact 109 when the wedge moves again to the right and moves the low portion of the track' into register with the roll 115.

From Athe above it will be seen that l have provided means for simultaneously welding the ends ot.' a plurality of tubes to the side of another tube and also that the control ol the tubes and the control of the welding operation is automatic.

l' claim: i i

-l. ln a Welding machine. the combination with ivorleholding means constructed to closingthe Welded circuit.-

realiser:

hold a plurality of separate elements with their ends in position to be welded to the side of another element, ot' electrical means to heat simultaneously the portions of said elements that are to be welded together` and means for controllingy automatically,7 the Worlr-holdingnieans and operating first to produce a slow relative movement of the heated endslof said elements toward the side of the other element and then to give a quick relative movement thereby to force the ends iirrnlv against said side.

2. lin a Welding machine, the combination with work-holding means constructed to hold a plurality of separate elements with 'their ends in position to be Welded to the side of another element, of electrical means to heat simultaneously the portions of said elements that are to be welded together, and means for controlling automatically the Work-holding means and operating to maintain a sparking Contact betwecnisaid ends of the elements and the side of the other element until the portions oi said side of the element to which the ends are to be welded has a Welding temperature and then to force the ends firmly against said side.

3. ln a Welding machine, the combination with means to supportv a plurality of tubes in parallel relation, olf means to support another tube in position to be welded to the ends of the parallel tubes, a separate welding circuit for heating each tube end and the portion of the tube side 4to which said end is to be Welded, and means to move said parallel tubes siniultaneously` against the side of the other tube.

` 4l. ln a welding,l machine, the combination with means to support a plurality of tubes in parallel relation. of means to support another tube in position to be Welded to =the ends of the parallel tubes, means constituting a separate circuit-lor heating each tube end and the ortion of the side ot the other tube to Whicli the tube endis to be Welded, and means 'for operatingr the tube-supporting means to cause a sparking Contact to be maintained between the ends o the tubes and 'the side ol' the other tube 'for an interval of time suicient to permit the side 'ot the tube to be brought to Welding temperature and then to force the tube ends against the side of the tube.

ln a welding machine, the`oonibinav tion with tubeefupperting mearsnconstructed to support a plurality of tubes in parallel relation. of means to support another tube in position to be Welded to the ends ol the parallel tubes, said supporting means including a contact to engage each tube' End and a plurality of contacts, one fo'each tube end, engaging the side of the other tube, a separate Welding circuit jfor each contact that engages a tube en d and the i corresponding Contact that engages the tube of the other tube andthen to .give the con- I 'tacts of each pair a quick relative movement toward. each other to press the tubes Arirrnly into welding' contact.

l5. in a welding machine, the combination with a plurality ot pairs of contacts constructed to hold the ends of a `plurality of tubes in close proximity to the side ot another tube, Aoi a weldingr transformer connected to each pair ot' contacts, and means for producing a relative movement of the contacts oi each pair towards each other by which said contacts have first a slow relative inoyernent thereby to produce` a sparking contact between the end ot' each of said plurality of tubes and the side of the other tube and then to have a quick Vrelative Inovenient to produce the weld.

16. ln a Weldingmachine, he combination with a plurality of pairs of contacts adjustable toward and from each other and constructed to hold the ends of a plurality of tubes in close proximity to the side ot other tube, of a Welding transformer connected to each pair of contacts, and means for producing a relative movement of the contacts ot' each pair towards each other by whichsaid contacts havelirst a slow relative movementand then quick relative movement. Y' 'l 1f?. In a Welding machine, the combination with a plurality of tube-slde-engaging contacts, all of which are adapted to engage the side of a tube, of a siinilar number of tube end engaging contacts, each adapted to engage a tubemeans supportinir said contacts.v so that the tube end held in the latter Icontacts will be in close proximity to the side of the tube'supported in the tube-sideengagingw contacts, ineens to cause a current to pass between each tubeend-engagging contact and the corresponding tubeside-engaging contact, and ineens to nroduce a slow relative movement of the tube-sideengaging contacts and the tube-end-engaging contacts toward each other Wl'ile said current is operative..

i8. ln a Welding Inachinathe combination with a plurality ot tube-side-engaging7 con; tacts, all ot `which are adapted to engage the side o'l' a tube, o' asimilar number of tubeend-engaging contacts, adapted toengage a tube end, means supporting said contact so that the tube ends held in the latter contacts Will be in close proximity to the side of the tube supported in thetube-side-engaging contacts, means to cause a current to pass between each tube-end engaging Contact and the corresponding tuM-side-engaging contact, and means to produce first a slow relative movement of the tube-side-engaging contacts and the tube-cnd-engaging contacts towards each other during which a sparking1 contact between the ends of the tube and the sides of the rst named tube is incense maintained and then to produce a quiclt relative movement of the tube-side-engagiug ontacts and the tube-'end-engaging contacts towards each other thereby to apply a u'eldinn; pressure to the tu" es.

19. ln a welding machine, the combina-A tion with a plurality ot' paigis of contacts, each pair comprising tubeside-engagins; contact and a tube-end-engaging contact, o"

means supporting the tube-side-engaugingI contacts in alineinent whereby they may all have contact with the side ot the saine tube, a Welding transformer connected to each pair oi contacts, and means to move the tubeside-engaging contacts simultaneously tc- Wardthe tube-end-engaging contacts thereby to maintain a sparking Contact between the ends olf tubes held in the tube-end-engaging contacts and the side ot the tube in the other contacts.

20. ln a Welding,- machine, the combination with a trarne, of means to support a tube, a plurality of tube-side-engaging contacts mounted thereon and adapted. to engage the side ot a tube, a tube support mounted on tie traine for adjustment toward and from said contacts and provided With means to sustain a plurality of tubes 'with their ends in position to be Welded to another tube carried by said contacts, and means to Weld said tube ends to said other tube.

21.y in a Welding machine, the combination with a fra-Ine, of a. plurality oP side-engaging contacts thereon adapted to engage the side of and sustain tube, a tube support mounted on the trarne and provided with means to sus-'tain in parallel relation a plurality of tubes with 'their ends in position.

to be Welded to the side of the first-named tubeyand means to Weld simultaneously said tube ends to said tube side.

22. In a Welding machine, the combination with. a freine, of a plurality of tubeside-engaging. contacts thereon, a tube support mounted on the 'trame and provided with adjustable means to sustain a plurality of tubes with their upper ends in position to be welded to the side ot' tube sustained by the tube-side-engaging contacts, and means to Weld simultaneously said tube ends to the side of the tube.

23. "in a Welding machine, the combination with a trarne of a plurality of Welding transformers adjustably -..niounted thereon tor adjustment toward and from each other,

a. pair of Welding contacts connected to and adjustable with each transformer, said contacts being constructedto hold the ends oi a plurality of tubes in position to be Welded to the side of another tube.

24. Aln-a. Welding machine; the combination With a trarne, of a plurality of welding transtoriners adjustably mounted thereon for adjustment toward and 'from each other, a pair r tube lll@ said .transformers simultaneously.

vso

In a welding machine, the combination with work-holding means constructed to hold a plurality of elements with their ends in position to be Welded to the side of another element, of means to heat simultaneously the portions of said elements that are to be welded together, and pneumaticallyoperated means for controlling the workholding means to cause the heated end of a plurality of elements to be forced simultaneously against the side-of the other elements thereby' -to weld simultaneously said ends of said side.

26. In a weldin machine, the combination with work-hol y means constructed to hold a plurality of elements with their ends in position to be welded to the side of another element, of means to heat simultaneously the ortiuns of said elements that are to be wel( ed together, and pneumatically-operated means for controlling the work-holding` means and operating first to produce a slow relative' movement of the heated ends of said elements toward the side of the other element and then to 'give a quick relative movement thereby7 to force the ends firmly against said side.

27. In a weldin, machine, the combination'with tube-hol ing means constructed to hold a plurality of tubes with their ends in position to be welded to the side of another "tube, of means to heat simultaneously said ltube ends and the tube side to which the ends are to be welded, and pneumatically-controlled means operating to maintain a sparking contact between said tube ends and the tube side, and subsequently to move the tube ends firmly against the tube side.

28. In a welding machine, the combination with weldingk contacts constructed to hold the end of a tube in close proximity to the side of another tube., of means to cause a. welding current to pass from one contact to the other, and pnenmatically-controlled means fbr determining the relative position of said contacts, said means operating first to give the contacts a gradual relative movement toward each `other thereby to maintain a sparking contact between said tube end and the side of the other tube and then to give said contacts a quick relative movement thereby to press the tubes firmly into welding contact.

29. In a welding machine, the combination with tube welding contacts constructed to hold the end of a tube n close proximity to the side of another tube, of means to cause, a welding current to pass from one to the other contact, means for controlling the relative position of said contacts which comprises a cylinder, a'plunger therein, pneumatic means to actuate the plunger, and a plunger-restraining device operating first to permit a slow movement only ofthe plunger and subsequently to permit a rapid movement thereof. i i

. 30. In a welding machine, the combination with welding contacts constructed to hold the end of a tube in close proximity to the side of another. tube, of means to cause a welding current to pass from one contact to the other, means controlling the'relative position of said contactscomprising a cylinder containing a liquid, a `plunger therein, means to move the plunger in the cylinder,

said cylinder having a discharge pipe, and

means operating during the first part of the movement of the piston to restrict the passage of liquid through the discharge pipe and during the latter portion of said movement to allow free passage of the liquid therethrou h'.y y A 31. n a weldinzl machine, the combination with a plura ity of pairs of contacts constructed to hold the ends of a plurality of tubes in close proximity to the side of another tube, of means to cause a welding current to pass from one to the other contact of each pair, a wedge device for producing relative movement of'the contacts of4 each pair toward each other, and means to actuate said Wedge device thereby to give the contacts first a slow relative movement to )roduce a sparking contact between the en of each of said plurality of tubes and the side of the other tube, and then to give said contact a quick relative movement to produce the weld.

32. In a weldin machine, the combination with a pluraity of pairs of contacts constructed to hold the ends of a plurality of tubes in close proximity to the side of another tube, of means to causea welding current to pass from one to the other contact of each pair, a wedge device for producing a relative movement of the contacts of each pair toward each other, a cylinder, a plunger therein connected to the wed 4e device, means to move the cylinder in tie plunger, and .means operating to retard( the initialmovement of the plunger whereby the contacts will have a slow relative movement toward each other and a sparking 'conztac'f will be maintained between each tube end' and the side of the other tube, and means to render the retarding means ino final movement of the p unger whereby the contacts have a quick movement toward each FRANCIS G. sans.

rative during the v 

